As shown in FIG. 1A, an electrical bulb and socket assembly includes a lamp 10 and a socket 12 with a hollow interior 14 for receiving the lamp 10. The lamp 10 includes a rectangular base 16 that carries a bulb 17. The base 16 has two sides 18 and two ends 20. A plug portion 22 extends from the base 16 and has electrical contacts 24 that extend into the interior of the bulb to a filament 26. Protrusions 28 extend outwardly from the ends 20 of the base. The base may include grooves 30 extending along the sides 18.
The socket 12 includes two pieces 32, 34 that are aligned with each other, two side walls 36 and two end walls 38. The side walls 36 have fingers 40 for engaging one of the grooves 30 of the lamp base. The lamp 10 is fastened to the socket 12 by inserting the lamp base 16 into the socket interior 14. As the lamp is inserted into the socket, the side surfaces 18 of its base 16 move the side walls 36 of the socket 12 outwardly until the fingers 40 snap into the grooves 30.
FIG. 1B shows another form of socket and bulb assembly, which is from a motor vehicle. A socket 42 that receives the lamp 10 includes side walls 44 with fingers 46 which snap into the groove 30 of the lamp base.
Double filament bulbs (not shown) may be used rather than single filament bulbs such as when bulbs with a blinking feature are desired. The protrusions of double filament bulbs have a narrower width than the protrusions of single filament bulbs. Therefore, in many cases single filament bulbs cannot normally be inserted into sockets intended to receive double filament bulbs. Different protrusion widths are used in some applications to ensure the use of bulbs having a particular number of filaments to avoid exceeding the intended wattage of the bulb.
In landscape lighting, it is desirable to design the bulb and socket assemblies to be small and reliable. The socket of FIG. 1A is undesirable because it is made of two pieces 32, 34. As a result of this two-piece construction, the socket body halves may be misaligned during fabrication of the socket, which may result in poor electrical contact during use. The socket construction of FIG. 1B is undesirable since the side fingers 46 make it difficult to form the socket small enough for landscape lighting. Moreover, since the fingers 40, 46 of both sockets 12, 42 have a relatively complex shape, the sockets are undesirable in view of excessive tooling costs required for their manufacture.